Aircraft: COMMERCIAL FIXED WING
Phase of flight: Cruise
Anomaly: ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy

Aircraft X; was on the CORRL STAR landing SFB. Aircraft X checks in level at 5;000. There is an un-tagged target Aircraft Y in their proximity at 5;900. At that time; they are not in conflict; and the targets do not appear to be on a course to merge.This area is Class E airspace; there is no requirement to be in contact with ATC; and it is a practice area for flight schools. Yes; this seems extremely unsafe; and it is! We have numerous commercial aircraft; loaded with potentially over 100 human lives; going through a VFR practice area all day; every day and nothing is done to stop it.In this practice area; you can expect to see aircraft doing such things as stalls; steep turns; rapid altitude changes; just to name a few.After assigning Aircraft X a runway assignment and seeing no traffic that they are in immediate conflict with I move onto another task. Aircraft Z; cold calls me requesting VFR practice approaches. I get them a code and assign them the code of XXXX. I wait a few seconds; and they aren't tagging up. So now; I ask the call sign of the Aircraft Z requesting approaches; the aircraft tells me and that's when I see the primary target change to a code of XXXX. I identify the aircraft; however; it won't tag up. I'm diagnosing why the target won't tag up and discover it's because they filed an IFR flight plan to be picked up in the air. So now there are 2 codes for this aircraft in my tab list. While I'm trying to delete the IFR code; Aircraft X keeps up and states they are responding to a TCAS/RA. I immediately did issue a traffic alert; but it was too late.After looking at the replay; I watched the targets merge; and what the playback showed was the in-tagged target made a hard-left hand turn; and descended rapidly causing the TCAS/RA. It appears the the target was almost diving at the aircraft and 'buzzing' it.The Aircraft X company itself; has identified the area between OMN and SFB as the area they receive the most TCAS/RA's in. But yet; we still fly them through there knowing this! Why? We issue multiple traffic advisories and traffic alerts in the area throughout the day. It isn't a secret this is a dangerous area. What would you expect; a major VFR practice area placed right in the middle of a published STAR; and at the published STARs altitude. With no airspace (Class C; Class B) protecting the aircraft.This isn't the first time this has happened; and if nothing is done it won't be the last time. The risk for a mid-air catastrophe in the area is extremely high. Something needs to be done. My recommendation is either move the practice area or change the STAR. We have 2 STARs into SFB; one over OMN and one over OCF. This event happen on the OMN STAR. The other STAR (OCF); is much safer; but yet we continue to receive multiple Aircraft X aircraft over the OMN STAR. In fact; the majority of the Aircraft X [company aircraft] are assigned the OMN STAR! I know; it doesn't make sense; but this is done all day every day.Now the provider (F11); the user Aircraft X [Company] has identified a significant safety risk to the FAA; and yet we are still in this predicament.Stop using the OMN STAR; that is my recommendation! Unless weather or other safety factors are more dangerous than this. I would be hard pressed to find a more dangerous spot than this.Also; flight schools should be picking up their airborne IFR with us and telling us on initial contact they have one on file. This will prevent 2 codes being generated for the same aircraft and aircraft automatically tagging up when assigned a code. We are going to work with them locally to see if they will start doing this. F11 Controller reported an unsafe scenario with two aircraft that were in a conflict due to a STAR and a VFR practice area being in close proximity.